COMSOL and WUFI results for the moisture content of the exterior softwood and of the total construction for two investigated versions of a timber flat roof.

Calculating time-dependent heat and moisture transports trough building components are important tasks in the area of building physics. A well known and worldwide used commercial software for this is WUFI®. From the scientific point of view the restricted access to governing equations is nevertheless a drawback of this software. In the present paper it is shown how the physical approaches used in WUFI are implemented in COMSOL Multiphysics. The COMSOL model is evaluated with two different benchmarks and WUFI results itself. It is shown, that the COMSOL model delivers good results in accordance with the benchmarks and with WUFI. However, slight deviations between COMSOL and WUFI results can occur if the moisture load on the construction is very high.